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Does Sampling Time Matter? Relationships of Circulating Metabolites at Various Neonatal Sampling Times in Beef Calves
Monday, March 14, 2016
Grand Ballroom - Foyer (Community Choice Credit Union Convention Center)
Jill M. Larson
,
Division of Animal Sciences, University of Missouri, Columbia, MO
Brian L. Vander Ley
,
Department of Veterinary Medicine and Surgery, University of Missouri, Columbia, MO
Samantha M. Bolen
,
Division of Animal Sciences, University of Missouri, Columbia, MO
Natalie B. Duncan
,
Division of Animal Sciences, University of Missouri, Columbia, MO
Allison M. Meyer
,
University of Missouri, Columbia, MO
Abstract Text: The objective of this study was to evaluate the relationships of neonatal sampling times for the analysis of circulating blood urea nitrogen (BUN), glucose, total protein, and globulin. A total of 66 fall-calving beef cows and heifers were monitored during calving, and calf blood samples were obtained from a subset (n = 24; average age = 4.4 ± 0.5 yr; average BCS = 5.2 ± 0.1; average calving date = September 11, 2015). Jugular blood samples were obtained from 8 bull and 16 heifer calves at 0, 6, 12, 24, 48, and 72 h postnatally for serum BUN, plasma glucose, serum total protein, and serum globulin analysis. Samples at 0 h were obtained prior to colostrum intake but after standing. Correlations were determined between each sampling hour within metabolite (Table 1). Metabolites at 0 h were correlated with few other sampling times. However, samples collected at 6 h had moderate or strong positive correlations with samples from 12 to 48 h. In general, there were a greater number of positive relationships in metabolites from consecutive sampling times. In conclusion, a consistent blood sampling time is necessary for determination of metabolite concentrations in neonatal beef calves, especially in pre-colostral samples. These data suggest that circulating metabolites at neonatal sampling times are more related after colostrum consumption.
Table 1. Correlation of postnatal sampling times (h) for serum BUN, plasma glucose, serum total protein, and serum globulin concentrations (mg/dL) in beef calves through 72 h
|
0 vs. 6
|
0 vs. 12
|
0 vs. 24
|
0 vs. 48
|
0 vs. 72
|
6 vs. 12
|
6 vs. 24
|
6 vs. 48
|
BUN
|
0.63**
|
0.30
|
0.09
|
0.04
|
-0.08
|
0.88**
|
0.57**
|
0.23
|
Glucose
|
0.69**
|
-0.07
|
0.02
|
0.39*
|
0.11
|
0.45*
|
0.43*
|
0.38*
|
Protein
|
0.19
|
0.15
|
0.18
|
0.03
|
-0.10
|
0.74**
|
0.45**
|
0.57**
|
Globulin
|
-0.12
|
-0.23
|
0.18
|
0.01
|
0.16
|
0.64**
|
0.44**
|
0.52**
|
|
|
|
|
|
|
|
|
|
|
6 vs. 72
|
12 vs. 24
|
12 vs. 48
|
12 vs. 72
|
24 vs. 48
|
24 vs. 72
|
48 vs. 72
|
|
BUN
|
0.11
|
0.83**
|
0.52**
|
0.45*
|
0.75**
|
0.57**
|
0.84**
|
|
Glucose
|
-0.29
|
0.59**
|
0.04
|
-0.47*
|
0.34
|
0.15
|
0.24
|
|
Protein
|
0.38*
|
0.84**
|
0.90**
|
0.40
|
0.97**
|
0.10
|
0.14
|
|
Globulin
|
0.21
|
0.85**
|
0.90**
|
0.40
|
0.98**
|
0.71**
|
0.71**
|
|
**P ≤ 0.05, *P ≤ 0.10
Keywords: colostrum, metabolites, neonates